Automatic optical inspection (AOI) systems use image processing and dedicated algorithms to inspect the surfaces of a PCB or a wafer in order to recognize defects on this surface. AOI systems compare an image of each die, or each suit (which includes number of dies or part of a die), or a whole wafer with a reference image in order to recognize differences that are suspected as defects. The AOI system is designed to use algorithms and predetermined criteria, to decide and to report which different is a defect.
The AOI process is done according to a recipe. A recipe includes, inter-alia, a detection-policy, reporting-policy and a reporting-policy. The detection-policy is a definition of which algorithms to use and a definition of the parameters of each algorithm. The reporting-policy is made by defining set of specific names of defect classes for reporting during inspection of lot of wafers. The inspection-policy is a definition of the behavior of the system during inspection; this policy is built up from set of pre-defined logical rules that guide the system what to do in each specific case.
The present invention provides a method and a system for establishing a recipe for testing a specific kind of wafer. The present invention provides some advantages. The present invention enables to decrease the recipe preparation time, enables to decrease the inspection results review time and enables to increase the utilization of wafer inspection machine. Moreover, the present invention enables recipe portability. The recipe is prepared on an off-line system and then it can be copied to a plurality of wafer inspection machines, which also ensures the similarity of the inspection criteria and rules of multiple inspection sites.